Dimers of nicotinamide adenine dinucleotide: New evidence for the structure and the involvement in an enzymatic redox process

• Published in: Bioorganic chemistry Vol. 9; no. 3; pp. 342 - 351
• Main Authors: Carelli, Vincenzo, Liberatore, Felice, Casini, Antonio, Mondelli, Rosanna, Arnone, Alberto, Carelli, Italo, Rotilio, Giuseppe, Mavelli, Irene
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 1980
• ISSN: 0045-2068; 1090-2120
• DOI: 10.1016/0045-2068(80)90044-9

The composition and the structure of the product from the known electrochemical dimerization of the NAD + have been conclusively demonstrated. A detailed analysis of the 1H and 13C nmr spectra has in fact led to the conclusion that the product contains three diastereoisomeric dimers of the 4,4′-tetrahydrobipyridyl type. Furthermore, the cytoplasmic fraction obtained from a standard mitochondrial preparation of rat liver has been shown to catalyze the oxygen uptake by the dimers. A 1 : 1 molar ratio of the reagents in the redox process is indicated by manometric data on oxygen uptake complemented by spectrophotometric analysis of the oxidized substrates, suggesting that H 2O 2 is the reduction product. NAD + was identified as the oxidation product by an enzymatic method.